Gun sling



FIG. 1 is a perspective view of a gun sling showing my new design, the broken lines therein being shown for illustrative purposes only;

FIG. 2 is a top plan view thereof;

FIG. 3 is a side elevation thereof;

FIG. 4 is a bottom view thereof;

FIG. 5 is a front end view; and,

FIG. 6 is a back end view. 

The ornamental design for a gun sling, as shown and described. 